TOKYO, Oct 31 (Reuters) - Japan's Nikkei stock average surged to a seven-year high and the yen tumbled to its lowest since early 2008 against the dollar on Friday as the Bank of Japan caught markets flat-footed with its surprise monetary easing decision.
The Nikkei surged over 5 percent to hit 16,455.84, its highest since November 2007.
The dollar jumped more than 1 percent to hit 110.69 yen , its highest since January 2008.
The BOJ unexpectedly eased monetary policy on Friday in a 5-4 vote, due to concerns that a decline in oil prices would weigh on consumer prices and delay a shift in sentiment away from deflation.
The central bank decided to increase the pace at which it expands base money to about 80 trillion yen ($723 billion) per year. Previously, the BOJ targeted an annual increase of 60-70 trillion yen. (1 US dollar = 110.5900 Japanese yen) (Reporting by Shinichi Saoshiro and Ayai Tomisawa; Editing by Prateek Chatterjee)